This invention relates to cord holding devices and particularly those whose function is to operate with venetian blinds or wooden shades. The term automatic is utilized to denote the designed reluctance of this device to permit unabated downward movement of the shade structure.
Various attempts have been made to provide a cord locking device of the above-mentioned type. Those prior assemblies illustrate complex structures incorporating variously positioned pulleys or wedges which restrict the movement of the pull cord. The number of moving parts as well as the difficulty of use often resulted in failure after a short period of time, in addition, cord wear was readily apparent in the previous attempts because of the continued engagement between the pull cord and gear teeth on pawls within the locking device. Prior devices also failed to solve the problems of shade crashing which was likely to occur when an individual operating the cord locking device let go of the cord.